IEC 61466-2:1998/AMD2:2018

IEC 61466-2 ®
Edition 1.0 2018-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
A MENDMENT 2
AM ENDEMENT 2
Composite string insulator units for overhead lines with a nominal voltage
greater than 1 000 V –
Part 2: Dimensional and electrical characteristics

Isolateurs composites destinés aux lignes aériennes de tension nominale
supérieure à 1 000 V –
Partie 2: Caractéristiques dimensionnelles et électriques

IEC 61466-2:1998-08/AMD2:2018-05(en-fr)

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IEC 61466-2 ®
Edition 1.0 2018-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
A MENDMENT 2
AM ENDEMENT 2
Composite string insulator units for overhead lines with a nominal voltage

greater than 1 000 V –
Part 2: Dimensional and electrical characteristics

Isolateurs composites destinés aux lignes aériennes de tension nominale

supérieure à 1 000 V –
Partie 2: Caractéristiques dimensionnelles et électriques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.080.10; 29.240.20 ISBN 978-2-8322-5670-1

– 2 – IEC 61466-2:1998/AMD2:2018
 IEC 2018
FOREWORD
This amendment has been prepared by IEC technical committee 36: Insulators.
The text of this amendment is based on the following documents:
FDIS Report on voting
36/427/FDIS 36/429/RVD
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC website under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
_____________
INTRODUCTION to Amendment 2
Amendment 2 implements the introduction of UHV (ultra-high voltage) applications and the
relevant characteristics of composite insulators.
1 Scope
Replace the first paragraph with the following new text:
This part of IEC 61466 is applicable to composite string insulator units with a specified
mechanical load (SML) of 40 kN to 600 kN for AC overhead lines with a nominal voltage
greater than 1 000 V and a frequency not greater than 100 Hz.
Replace the fourth paragraph with the following new text:
This standard specifies values for electrical and dimensional characteristics for composite
insulators for overhead lines with a minimum lightning impulse withstand voltage (BIL) up to
3 100 kV and a specified mechanical load (SML) of 40 kN to 600 kN.
2 Normative references
Add the following new reference:
IEC TS 60815-3, Selection and dimensioning of high-voltage insulators intended for use in
polluted conditions – Part 3: Polymer insulators for a.c. systems

 IEC 2018
8 Field control and arc protection devices
Replace the existing text and Table 1 with the following new text and new Table 1:
For higher system voltages field control devices may be necessary. When such devices are
fitted on the insulators, the arcing distance in Table 1 shall be determined considering their
presence. If separate arc protection devices are used, the required additional striking distance
can be extrapolated.
Table 1 – Designation and characteristics of composite insulators
Specified Standard Minimum Minimum dry Highest voltage for
mechanical loads lightning creepage arcing equipment based on
a d c
Designation (SML) impulse distance distance 27,8 mm/kV unified specific
d
(typical values in withstand creepage distance
b
white area) voltage
kN kV mm mm kV
CS(SML)(XZ)-
40 70 100 120 160 210 60 195 100 12
60-195
CS(SML)(XZ)-
40 70 100 120 160 210 75 195 125 12
75-195
CS(SML)(XZ)-
40 70 100 120 160 210 75 280 125 17,5
75-280
CS(SML)(XZ)-
40 70 100 120 160 210 95 195 160 12
95-195
CS(SML)(XZ)-
40 70 100 120 160 210 95 280 160 17,5
95-280
CS(SML)(XZ)-
40 70 100 120 160 210 95 385 160 24
95-385
CS(SML)(XZ)-
40 70 100 120 160 210 125 385 210 24
125-385
CS(SML)(XZ)-
40 70 100 120 160 210 145 385 240 24
145-385
CS(SML)(XZ)-
40 70 100 120 160 210 145 580 240 36
145-580
CS(SML)(XZ)-
40 70 100 120 160 210 170 580 285 36
170-580
CS(SML)(XZ)-
40 70 100 120 160 210 250 835 435 52
250-835
CS(SML)(XZ)-
40 70 100 120 160 210 325 1 160 570 72,5
325-1160
CS(SML)(XZ)-
40 70 100 120 160 210 450 1 970 815 123
450-1970
CS(SML)(XZ)-
40 70 100 120 160 210 450 2 320 815 145
450-2320
CS(SML)(XZ)-
40 70 100 120 160 210 550 1 970 1 005 123
550-1970
CS(SML)(XZ)-
40 70 100 120 160 210 550 2 320 1 005 145
550-2320
CS(SML)(XZ)-
40 70 100 120 160 210 550 2 720 1 005 170
550-2720
CS(SML)(XZ)-
40 70 100 120 160 210 650 2 320 1 195 145
650-2320
CS(SML)(XZ)-
40 70 100 120 160 210 650 2 720 1 195 170
650-2720
CS(SML)(XZ)-
40 70 100 120 160 210 650 3 920 1 195 245
650-3920
– 4 – IEC 61466-2:1998/AMD2:2018
 IEC 2018
Specified Standard Minimum Minimum dry Highest voltage for
mechanical loads lightning creepage arcing equipment based on
a d c
Designation (SML) impulse distance distance 27,8 mm/kV unified specific
d
(typical values in withstand creepage distance
b
white area) voltage
kN kV mm mm kV
CS(SML)(XZ)-
40 70 100 120 160 210 750 2 720 1 395 170
750-2720
CS(SML)(XZ)-
70 100 120 160 210 300 750 3 920 1 395 245
750-3920
CS(SML)(XZ)-
70 100 120 160 210 300 850 3 920 1 585 245
850-3920
CS(SML)(XZ)-
70 100 120 160 210 300 950 3 920 1 775 245
950-3920
CS(SML)(XZ)-
70 100 120 160 210 300 1050 3 920 1 970 245
1050-3920
CS(SML)(XZ)-
160 210 300 400 1050 4 800 2 100 300
1050-4800
CS(SML)(XZ)-
160 210 300 400 1175 5 795 2 400 362
1175-5795
CS(SML)(XZ)-
160 210 300 400 550 600 1425 6 720 2 800 420
1425-6720
CS(SML)(XZ)- e
160 210 300 400 550 600 1550 8 800 3 800 550
1550-8800
CS(SML)(XZ)- e
160 210 300 400 550 600 1800 8 800 4 000 550
1800-8800
CS(SML)(XZ)- e
160 210 300 400 550 600 2100 12 800 5 500 800
2100-12800
CS(SML)(XZ)- e
160 210 300 400 550 600 2550 17 600 6 500 1 100
2550-17600
CS(SML)(XZ)- e
160 210 300 400 550 600 2700 19 200 8 000 1 200
2700-19200
CS(SML)(XZ)- e
160 210 300 400 550 600 2900 19 200 8 000 1 200
2900-19200
CS(SML)(XZ)- e
160 210 300 400 550 600 3100 19 200 8 500 1 200
3100-19200
a
The letters CS followed by a number indicating the specified mechanical load (SML) in kN (XZ) are the coupling
code letters in accordance with IEC 61466-1, followed by the lightning impulse withstand voltage (BIL) in kV
and the creepage distance in mm, for examples, CS(160)(CC)-550-2480.
b
When using arc protection devices, greater values of lightning impulse withstand voltage for the insulator may
be specified by the customer, for voltage levels of U > 245 kV the switching withstand voltage becomes the
m
dominating design criterion.
c
The minimum arcing distance is specified considering conductor-structure gap characteristics, rather than a
maximum section length (distance between couplings), because the diversity of end fitting types and materials
makes it impractical, at the time of publication of this document, to standardize the section length.
d
This column is given for information only and the values refer to “light” polluted environment. For
supplementary information on creepage distance see IEC 60815-3 and Annex A.
e
These figures are indicative for normal altitude (< 1 000 m) and not considering switching impulse strength.
Thus these values can be higher or lower if proven by the applicable withstand tests of the specific string or set
configuration considering grading and power arc protection devices, especially for different switching withstand
voltage ratings.
 IEC 2018
Annex A
Replace the existing text with the following new text:
Table 1 gives values of the highest voltage for equipment U based on a unified specific
m
creepage distance of 27,8 mm/kV (line to earth). Experience to date indicates that this unified
specific creepage distance is satisfactory for areas where pollution performance is not
considered to be a critical factor. The user will need to consider any change of creepage
distance (increase or even decrease) necessary to ensure adequate performance for the
environmental conditions (e.g. pollution level, exposure time, wetting conditions) encountered
in each area of application. Creepage distance for composite insulators shall be designed in
accordance with IEC TS 60815-3.

____________
– 6 – IEC 61466-2:1998/AMD2:2018
 IEC 2018
AVANT-PROPOS
Le présent amendement a été établi par le comité d'études 36 de l'IEC: Isolateurs.
Le texte de cet amendement est issu des documents suivants:
FDIS Rapport de
...